Modeling process-induced cell damage in the biodispensing process

Emerging biomanufacturing processes involve incorporation of living cells into various processes and systems by employing different cell manipulation techniques. Among them, biodispensing, in which the cell suspension is extruded via a fine needle under pressurized air, is a promising technique because of its high efficiency. Cells in this process are continually subjected to mechanical forces and may be damaged if the force or manipulation time exceeds certain levels. Modeling cell injury incurred in these processes is lacking in the literature. This article presents a method to quantify the force-induced cell damage in the biodispensing process. This method consists of two steps: first is to establish cell damage laws to relate cell damage to hydrostatic pressure/shear stress; and the second is to represent the process-induced forces experienced by cells during the biodispensing process and apply the established cell damage law to represent the percentage of cell damage. Schwann cells and 3T3 fibroblasts were used to validate the model and the comparisons of experimental and simulation results show the effectiveness of the method presented in this article.